Faktor

The impact factor of a scientific journal is a measure
reflecting the average number of citations to articles
published in science journals. For this task we are using a
simplified formula for calculating the impact
factor:

\[ \frac{\text {Total
count of citations received by articles published in the
journal}}{\text {Total number of articles published}} \]

Rounding is always performed upwards. For example the impact
factor of the “Journal for ore research and time wasting” that
published $38$ articles
cited $894$ times is
$894 / 38 = 23.53$
rounding up to $24$.

You are the editor of one scientific journal. You know how
many articles you are going to publish and the owners are
pushing you to reach a specific impact factor. You are
wondering how many scientists you will have to bribe to cite
your articles to meet the owners demands. Since money is tight
you want to bribe the minimal amount of scientists. Each bribed
scientist buys you a single citation.

Input

First and only line of input will contain $2$ integers, $A$ ($1
\leq A \leq 100$), the number of articles you plan to
publish and $I$
($1 \leq I \leq 100$), the
impact factor the owners require.

Output

The first and only line of output should contain one
integer, the minimal number of scientists you need to
bribe.